Advice on buying a wheel for touring/ general specs

[Maddo1919]

Hi,

Firstly I know this bike is cheap but I have a Carrera Vengeance and if I had the dollar I would ditch it in a heartbeat but I'm planning a bike tour soon and will be carrying a lot of weight on the back around 20kg. I want to upgrade my rear wheel to some sun rhino's as I have heard that these are perfect for the job and I have found one for sale with the following specs

I have found 26" sun rhino lite, shimano deore Xt Hub and a 9 speed freehub and 6 botlt disc hub (I currently have an 8 speed cassette but a lot of information seems to suggest these will fit) I am planning to buy the wheel and then take it to the bicycle kitchen where they will teach me how to install but I just want to know before buying if this is the correct wheel the job

 

[Vantage]

As long as the original rim isn't too worn it'll be perfectly fine for touring on. Mountain bike wheels are built to take abuse. As long as it's ok you'd be better off spending that money on lighter touring gear.
Your main worry should be the rear racks weight limit and heel clearance. Some can't take 20kg. At least not safely anyway.
Which year is your bike by the way? From googling, the latest models are specced with 27" wheels, not 26".